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Cellular aspects of the distinct M protein and SfbI anchoring pathways in Streptococcus pyogenes

Assaf Raz1, Susanne R Talay, Vincent A Fischetti

  • 1Bacterial Pathogenesis and Immunology, Rockefeller University, New York, USA. araz@rockefeller.edu

Molecular Microbiology
|April 20, 2012
PubMed

Insights

Surface proteins like M protein and SfbI are crucial for Streptococcus pyogenes survival. Their anchoring is linked to cell division, offering potential targets for new anti-infective agents.

Area of Science:

  • Microbiology
  • Cell Biology
  • Bacterial Pathogenesis

Background:

  • Surface proteins are essential for Streptococcus pyogenes survival in vivo.
  • The precise mechanisms of surface protein translocation and anchoring are not fully elucidated.
  • M protein and SfbI are key surface proteins targeted for anchoring by sortase A.

Purpose of the Study:

  • To investigate the cellular features and spatial regulation of M protein and SfbI anchoring in Streptococcus pyogenes.
  • To determine the relationship between cell division processes and surface protein anchoring.
  • To explore potential novel targets for anti-infective agents based on surface anchoring mechanisms.

Main Methods:

  • Simultaneous observation of M protein and SfbI anchoring throughout the cell cycle.
  • Analysis of protein translocation independent of sortase A.
  • Investigating the effects of methicillin-induced peptidoglycan synthesis changes.
  • Examining the impact of DivIVA overexpression on surface protein levels.

Main Results:

  • M protein and SfbI are anchored simultaneously across the cell cycle.
  • M protein anchors rapidly at the septum, while SfbI gradually accumulates at the poles.
  • Sortase A is not essential for the translocation of M protein or SfbI.
  • Disruptions in peptidoglycan synthesis or cell division regulators affect M protein and SfbI anchoring differently.

Conclusions:

  • Cell division regulation is closely interconnected with surface protein anchoring in Streptococcus pyogenes.
  • Distinct spatial regulation mechanisms exist for M protein and SfbI anchoring.
  • Understanding these anchoring pathways may reveal new targets for developing anti-infective therapies.

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